Marine sounding cocks, essential components in the maritime industry, are specialised valves used for measuring the level of liquid in a ship's tank. These devices play a crucial role in ensuring the safety and stability of vessels by providing accurate readings of fuel, water, and cargo liquids. The term "sounding cock" refers to its function of allowing a sounding tape to be inserted into the tank to measure the fluid level. They are typically made of durable materials like brass or bronze to withstand harsh marine environments and resist corrosion.